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2A Flue elbow
2B Vertical fl ue adaptor
3 Cap
18.2.3
Maximum rate check and adjustment
To verify the maximum gas rate CO
2
setting the
appliance must be checked at the maximum rate.
• Activate the test mode "P.01" and set the value to 99? in
order to force the burner at P. max. See chapter "Specifi c
adjustment ► Appliance technical settings and parameter list
► Test modes".
• Wait approximately 5 minutes to read a stabilised CO
2
value.
• Check that the value is within the range specifi ed in table in
the “check” column.
24
28
Gas adjustment
G20
G31
G20
G31
Ratio
CO
2
case ON
9.2 ± 0.3 10.3 ± 0.3 9.2 ± 0.3 10.3 ± 0.3
<0.004
CO
2
case OFF
9.0 ± 0.2 10.1 ± 0.2 9.0 ± 0.3 10.1 ± 0.2
<0.004
• If the combustion reading is not within the acceptable values
and the integrity of the complete fl ue system and combustion
circuit seals have been verifi ed and the inlet gas pressure
(and gas rate) have been verifi ed, then, it will necessary to
adjust the combustion rate of the appliance.
Adjustment is made by turning the throttle an ⅛
of a turn, waiting 1 minute to allow the appliance
to stabilise before checking or making further
adjustments.
• Remove the sticker covering the “throttle” adjustment screw,
if fi tted.
• Rotate the “throttle” (1) (anti-clockwise to increase), to the
required CO
2
, refer to previous diagram and the “Setting”
column in the table.
• When you have fi nished, press the On/Off button to exit the
test modes.
• Remove the analyser probe and replace the cap on the
sampling point, replace the controls fascia, and the front
casing panel.
Remember to replace the sample point cap on
completion of the test.
18.2.4
Gas rate check
• Check the gas rates as described in the commissioning
section.
18.2.5
Completion
If it is not possible to achieve the required results for either the
combustion or gas rates, it will be necessary to complete a full
service of the appliance and then repeat the combustion check
procedure.
If after servicing and adjustment of the appliance the combustion
values are still unacceptable and after further remedial work has
been carried out, the appliance must be disconnected until the
CO/CO
2
ratio is acceptable.
• Advice can be sought from the Heatline Technical Helpline.
18.3 Servicing
If the Flame Picture, Combustion & Gas Rate
checks did not identify a problem then it will not be
necessary to remove the combustion chamber door.
All routine servicing requirements can be achieved by the
removal of the front panel.
• Position the control box into the service position.
• Before commencing with a service or replacement of parts,
isolate the boiler from the electrical and gas supplies.
18.3.1
Service interval record
• Refer to benchmark Service Interval Record at the rear of this
manual.
18.4 Silencer
3
1
2
Key
1 Silencer retaining screw
2 Fixed silencer
3 Removable silencer
• Remove the silencer retaining screws (1) and remove the
silencer (3).
• Clean the interior of the silencer with a dry cloth if necessary,
taking care not to damage the internal foam.
• Repeat the operation in reverse order to replace the silencer.
